Tag Archives: MC-750

Field Reports, News, Portable, POTA, QRP, Videos

Cabin POTA with the IC-705 and MC-750 at Gorges State Park!

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As I mentioned in this previous field report, my buddy Mike and I spent the third weekend of March at Gorges State Park (US-2732) in Sapphire, North Carolina. We had a great weekend of hiking and just hanging out. Of course, I fit in a few activations!

On the morning of Sunday, March 17, 2024, after a nice breakfast and beautiful sunrise, we started packing up. Since we rented a cabin this year, it was an easy process–especially since it was also raining lightly. While I love tent camping, I’m not the biggest fan of packing up a wet tent and gear because later in the day I have to attempt to dry it all out back home.

The cabin also made it very comfortable to do a little Parks on the Air (POTA) until the rain passed and we could start our hike.

I set up my MC-750 vertical next to the cabin.

Inside, assuming I might have more radio frequency interference (QRM) to deal with, I chose my Icom IC-705.

The cabin had a small side table attached to the wall which was the perfect spot to set up my station close to the front door and porch. The weather was very temperate that morning, so I simply left the front door of the cabin open while I operated.

I was correct about the QRM: its pervasive throughout most of the park and is due to arcing on the high-tension power lines that run through the site.

Other than the QRM, Gorges is an amazing park to do POTA.

While I played Parks on the Air, Mike caught up on a book he was reading. Neither of us were pressed for time, so it was a pretty laid-back morning.

QRM Mitigation

After hooking up the IC-705 to the MC-750 and turning it on, the QRM was not only audible–that unmistakable frying sound–but it was clearly visible on the IC-705’s color display.

The noise level was about S5-S6 and persistent.

The IC-705 is a 21st-century radio and I decided to use some of its 21st-century, SDR-powered features in order to improve the audio.

First, I turned on the Noise Blanker (NB). While this feature works best for pulse noises (engine noise and electric fences, in my experience) it also removes a layer of noise from persistent arcing as well.

Next, I also used the IC-705’s built-in DSP (Digital Signal Processing). By turning on the DSP, another layer of noise is removed.

With both NB and DSP engaged, the audio was much more pleasant and less fatiguing.

Keep in mind that even though the noise was minimized in the audio, it was still there in the receiver so this didn’t help much with recovering weak signals under the elevated noise floor. It just made playing radio much more pleasant! Continue reading Cabin POTA with the IC-705 and MC-750 at Gorges State Park! →

Antennas, Guest Posts, News, Portable, Reviews

Guest Post: Reviewing the Chelegance MC-750 (Part 1)

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Many thanks to Charles (KW6G) who shares the following guest post:

Product Review: Chelegance MC-750 Portable Ground Plane Antenna, Part 1

by Charles Ahlgren, KW6G

I recently purchased a Chelegance MC-750 portable ground plane antenna from DX Engineering.  Essentially, the antenna system provides a ¼ wave portable vertical antenna with 4 counterpoise wires that operates on 20 through 10 meters.  The antenna will also operate on 40 meters with the provided loading coil.  The manual states the antenna will support 6 meter operation, but no instructions are provided on how to do so.  30 meter operation is not supported.   It appears from our initial testing that no ATU is required.

Here are some of my thoughts on the antenna.

Product Description

The MC-750 comes with the following components:

  • GROUND ROD / ANT BASE
  • 50 CM ANT ARM
  • 5.2 M WHIP
  • 7 MHZ COIL
  • 4  COUNTERPOISE WIRES (radials)
  • COUNTERPOISE WIRE COLLECTOR BOARD
  • CARRY BAG

As provided, it is designed to operate on  the 40, 20, 17, 15, 12, and 10 meter bands without any modifications.  Six meters is also supported per the manufacturers manual, but no guidance on how to do that is offered in that document.   However, finding the proper length of radiator for 6 meters should be straightforward using a tape measure to set the proper whip length.

[Update: Chelegance notes that to operate 6 meters, simply extend the last segment only of the whip (see photo) and for 30 meters extend the last four segments of the whip and 15cm on the 5th segment (see photo).]

I checked the ground rod / antenna base with a magnet and confirmed it is made from stainless steel as both components are not magnetic; a characteristic of stainless.   Both the ground rod/ antenna base and the 50 cm antenna arm (which was also non-magnetic) had a hefty feel (together, they weigh about 2 pounds), therefore I think it safe to assume that these components are made of stainless steel.  Since most ops will undoubtedly use the antenna arm as an aid to inserting / extracting the ground rod into / from the ground, it seems a prudent decision by the manufacturer to have this piece fabricated from a strong, stiff  material such as steel.  The machine work used to fabricate these parts appears to be quite good – the fit and feel were excellent, with no sharp or ragged edges to cause problems in the field.

I measured the whip while set at the various position marks for 20 through 10 meters.  The band markings on the whip were accurate – giving a 1/4 wavelength radiator when combined with the 50 CM ant arm length…On 40 meters, the whip and rod measured about 1/8 wavelength.  The required the loading coil needs to be inserted between the whip and the rod (at approximately 1/10 the total 40 meter whip height above the base).  If you want to operate this antenna on 30 meters, it appears that you need to provide an extra 1.4  meter of additional rod as a quarter wavelength ground plane at 10.1 MHz  requires a 7.1  meter radiator.  Six meter operation would require a whip of around 4.7 feet.  With the whip fully collapsed, the length of the rod and antenna arm measures 40-1/4”.  Therefore, if 6 meter operation is contemplated, extending the whip about 16 inches from fully collapsed should suffice.  However, I don’t think that an antenna configuration such as that would be a very good performer unless it were elevated from ground level; or maybe it would be good for a SOTA activation? Continue reading Guest Post: Reviewing the Chelegance MC-750 (Part 1) →

Antennas, Field Reports, Morse Code, New Products, News, Portable, QRP

Taking the new Chelegance MC-750 vertical on a POTA activation at Lake James State Park

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Back in September, I was contacted by Jesse Chen (BD7LLY) who has been a long-time reader of QRPer.com. Jesse is also the founder of Chelegance (a.k.a. JNCRadio): a company that has been producing ham radio gear and accessories since 2020.

Jesse reached out and asked if I would consider evaluating a couple of the field portable antennas he designs and produces in China.

In truth, I get a lot–and I do mean loads–of requests to evaluate products and I pass on 97% of them. I only have so much time and I simply don’t bother with gear I think is unnecessary or that could be cheaply made.

Before replying to Jesse, I did a little research on Chelegance and discovered that DX Engineering now distributes their products. I decided that if DX Engineering liked the quality well enough to add Chelegance products to their catalog, then it must be up to a decent standard. I’ve never purchased anything sub-quality from DX Engineering.

I also like the fact that Jesse is a real amateur radio operator.

After checking back in with Jesse, he decided to send me two of his portable HF antennas: the M-104 and the MC-750. In full disclosure, he sent these to me at no charge–i.e. free–with the idea I could do a proper evaluation and share my thoughts both with him and with my readers.

He knew that both of these antennas had the potential to compliment my style of portable operating. I also told Jesse not to rush ship them to me as I was quite busy. I received both antennas at the end of October.

The first antenna I wanted to try was the MC-750.

The Chelegance MC-750

When I received the parcel from Jesse, I was very impressed with the MC-750’s custom soft-sided case. The stitching and quality of it are much better than I would have expected. The interior is custom designed to hold all of the MC-750 antenna components. There’s enough extra space in it, in fact, that I can also carry a 40′ RG-316 feedline inside.

Product Photo by Chelegance

The antenna basically consists of the following components in the supplied padded bag:

  • A heavy stainless steel ground spike and matching unit
  • 40 meter coil
  • 50 cm antenna arm/extension
  • 5.2 meter telescoping whip
  • 4 yellow counterpoise wires with a wire winder board

The price for the antenna system is $250 via DX Engineering and 219€ via WIMO. Moonraker in the UK is also a Chelegance distributor, but doesn’t seem to have the MC-750 listed in their inventory at time of posting (Dec 5, 2022).

The only antenna I have that might compare with the MC-750 is the Chameleon CHA MPAS Lite which is one of my favorite portable HF antennas for its quick deployment, and overall quality. For reference, the CHA MPAS Lite retails for about $360.

I thought the best way to test the MC-750 would be to take it on a POTA activation. Continue reading Taking the new Chelegance MC-750 vertical on a POTA activation at Lake James State Park →